Engine coolant distribution



Sept. 20, 1960 A. E.KOLJBE 2,953,126

ENGINE COOLANT DISTRIBUTION Filed Dec. 12, 1958 3 Sheets-Sheet 1 IN VEN T OR.

fi y/ Y I I I v ATTORNEY A. E. KOLBE ENGINE COOLANT DISTRIBUTION Sept. 20, 1960 Filed Dec 12. 1958 5 Sheets-Sheet 2 A T TOR/YE) P 1960 A. E. KOLBE 2,953,126

ENGINE COOLANT DISTRIBUTION Filed Dec. 12. 1958 3 Sheets-Sheet 3 IN VEN TOR.

A 7'7'ORNE):

Patented Sept. 20, 1960 ENGINE COOLANT DISTRIBUTION Adelbert E. Kolbe, Berkley, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Dec. 12, 1958, Ser. No. 780,111

2 Claims. (Cl. 123-4128) The invention relates to the distribution passages for coolant in an internal combustion engine and more particularly to the passages in the engine block and head. In internal combustion engines of the multi-cylinder type, there have usually been problems encountered in obtaining uniform cooling of each of the engine cylinders as well as the valves and spark plugs. It has been common practice to circulate a coolant such as water in series relation past each cylinder in a bank of cylinders. The coolant has also been circulated in series adjacent the valves for each cylinder. This type of circulation results in the first cylinder encountered by the coolant being cooled to the greatest extent and the last cylinder being exposed to considerably warmer coolant and therefore being cooled to a lesser extent. Similar cooling results have been obtained in the engine head when the engine is of the valvein-head type. This results in the last valves and the last cylinders being cooled running hotter than the first valves and first cylinders being cooled.

In attempts to overcome these objections, engines have been manufactured which distributed coolant to the cylinders and their associated valves in parallel relation so that, for example, the number one cylinder and the number one intake and exhaust valves are cooled by coolant which has not passed over the other cylinders and valves. While this has provided improved cooling results, it has been found in previously proposed systems that the cylinders and valves first cooled received a greater flow of coolant than the cylinder and associated valves last cooled. This resulted in stagnant hot spots at the rear of the engine. These hot spots are a clear indication of the lack of coolant flow to the rear of the engine.

It is now proposed to provide a coolant passage in the engine block with a passage section which leads directly from the coolant pump discharge to the rear end Wall of the engine and alongside the cylinders forming an engine bank. This portion of the coolant passage should be relatively large in cross section area so that a suflicient quantity of coolant is moved to the rear of the engine at all times. It is also proposed to so calibrate the coolant passages from the block to the passages in the head that coolant is forced to move to the rear of the engine without absorbing an undue quantity of heat energy from the cylinders passed by the coolant during its flow to the rear wall. The block coolant passage is so arranged that the cylinders are substantially surrounded by coolant flowing from the cylinder wall upwardly to the engine head and cooling the portion of the combustion chamber formed by the head as well as the valves and spark plugs. The parallel flow coolant system is therefore improved in that the majority of the coolant which cools any one cylinder is transmitted to that portion of the engine head containing the valves and spark plugs for that cylinder and they are in turn cooled, with each cylinder and valve set being exposed to coolant of substantially the same temperature. This results in more uniform engine cooling throughout. The passage leading to the cylinder head coolant passages from the engine block coolant passages are graduated so that the smallest passage is adjacent the block coolant entry passage and the largest passage is at the opposite end of the block coolant passage. The graduated passages therefore aid in forcing the coolant to circulate all the way to the engine rear wall with a substantially undiminished coolant flow.

In the drawings:

Figure 1 is an end view of a portion of an engine emhodying the invention and having parts broken away and in section.

Figure 2 is a view of the engine of Figure 1 having parts broken away and in section and taken in the direction of arrows 2--2 of Figure 1.

Figure 3 is a section view of the engine of Figure 1 taken in the direction of arrows 33 of Figure 2 and having parts broken away and in section.

Figure 4 is a section view of the engine of Figure 1 taken in the direction of arrows 44 of Figure 2 and having parts broken away and in section.

The engine 10 illustrated in the drawing is a six-cylinder in-line engine. The invention may also be applied to other engines such as V-block engines or opposed-cylinder engines. The engine 10 has an engine block 12 and a head 14 which is secured to the top of the block and separated therefrom by the conventional head gasket 16. Block 12 has a front end wall 18, a rear end wall 20, and side walls 22 and 24. A series of cylinders forming an engine cylinder bank is also provided intermediate these walls. Six cylinders are illustrated and identified v as cylinders 26, 28, 30, 32,34, and 36, respectively, from the front end wall to the rear end wall.

The engine block is also provided with an upper wall 38 which receives the cylinder head lower wall 40. The block lower wall 42 may define the upper portion of the engine crankcase. The engine is also providedwith conventional elements including the crankshaft 44, pistons 46, and connecting rods 48. A combustion chamber 50 is defined by each piston 46 and the head 14 and the inner wall of the associated cylinder. Each combustion chamber is provided with inlet and exhaust valves, the exhaust valve 52 being illustrated. A spark plug 54 is also provided for each combustion chamber. The valves are actuated by the conventional camshaft 56 and valve lifters 58.

A block coolant passage 60 is provided intermediate the block walls and the cylinders. The engine water pump may be mounted so that its discharge passage corresponds to the coolant entry passage 62 formed in the front end Wall 18. This passage is preferably rectangular in shape and extends throughout a substantial portion of the cross section area of coolant passage 60. The portion 64 of coolant passage 60 beyond entry 62 extends longitudinally of the engine block and adjacent one side of the cylinders to the inner surface of the rear wall 20. Portion 64 is preferably uninterrupted and substantially straight so that coolant entering at 62 may be conducted with a minimum of flow resistance to the rear Wall 20. Passage 60 also is provided with branch portions 66 leading around each of the cylinders so that the outer surface of each cylinder wall is substantially surrounded by coolant.

The block upper wall 38 is provided with a series of apertures 68, 70, 72, 74, 76, 78, and 82, which are connected with coolant passage portion 64 so that they bleed off a portion of the coolant flowing through this passage and transmit it to the coolant passages 84 in the engine head. Apertures 86 and 88 are also provided in the block upper wall and connect with coolant passage branches 66 opposite coolant passage portion 64. Apertures 68 through 82 are graduated in cross section area, with aperture 68 being the smallest and aperture 82 being the largest when coolant flow is from the front wall 18 toward rear wall 20, so that coolant flowing through entry '62 and coolant passage 64 will maintain a substantial coolant flow throughout the length of the block. The coolant reaching the end wall 2!! will have a substantial a sl nt flow Quh l ni e 8. an 2% t at a nantfhot, spots in area are eliminated. Apertures 86 and 8 8 aid in maintaining coolant flow transversely of .the bl ock so that eachof the cylinders is exposed to a substantial coolant flow.

The cylinder head is provided with apertures 90 which correspond to the apertures formed in the upper wall of n the block and connect with the head inlet passages .84 so that coolantparallel-fiow arrangement is maintained. Gasket 16 is also formed to permit the head apertures and the block apertures to connect with each other in fiOW relation. If desired, the graduated passages may be 'formed in the lower wall 4010f the engine head rather than in the upper wall 3816f the block, or the passages may be graduated in both walls. The coolant received by the head through the apertures passes forwardly 7 vided which will maintain more uniform coolant distribution, resulting in more uniform cooling of the cylin: ders and valves of acylinder bank. The distribution systern insures vehicle coolant fiow along the entire length of the block and head in order to prevent the creation of hot spots in some sections of the engine.

1. In an engine block, a longitudinally extending coolant passage formed therein and extending substantially the entire length thereof, said block having a coolant passage entry formed in one end, said entry having a cross-section substantially equal to the minimum crosssection of said coolant passage, and a series of coolant outlet passages connecting with said coolant passage in series flow relation. 7

2. In an internal combustion engine, an engine block comprised of a bank of cylinders and end walls and side walls and upper and lower Walls cooperating with said cylinders to define coolant passage means for conducting coolant to and from said cylinders, a cylinder head secured to said block and having a lower wall adjacent said block upper Wall and having coolant passage means formed therein defined in part by said head lower wall,

What is claimed is:

a one of said adjacent walls having a series of apertures formed .tl'ie reinand the other of said adjacent Wallshaving a corresponding series of apertures formed therein whereby said block coolant passage means and said head coolant passage means are connected in flow rellatinn,

one ot saidblock end walls having a coolant 'entry'aper ture formed therein and aligned with said block coolant passage means to provide a substantially straight man flow'to said other end wall thro ugh'said block coolant passage means. Y

'Short June '5, 1923 Rohrbacher et al ec. '2, 1958 

